Anti-cancer extract and compounds

ABSTRACT

The present invention relates to a new approach for treating a cancer or fibrosis, such as hepatocellular carcinoma, or liver fibrosis using an extract from a plant of  Graptopetalum  sp.,  Rhodiola  sp., or  Echeveria  sp., and prepared by extracting the plant with dimethyl sulfoxide (DMSO), its fraction or the compound isolated from the extract.

CROSS-REFERENCES

This application is a divisional application of U.S. patent applicationSer. No. 13/249,904 by Chi-Ying Huang, entitled “Anti-Cancer Extract andCompounds,” and filed on Sep. 20, 2011, the contents of which areincorporated herein in their entirety by this reference.

FIELD OF THE INVENTION

The present invention relates to a new extract and new compounds havinganti-cancer activities from a plant.

BACKGROUND OF THE INVENTION

Graptopetalum paraguayense (GP) is a Chinese traditional herb andpossesses several health benefits. According to its archaic Chineseprescription, GP is considered to have potentially beneficial effects byalleviating hepatic disorders, lowering blood pressure, whitening skin,relieving pain and infections, inhibiting inflammation, and improvingbrain function.

It was shown in the studies that the leaf extracts of GP could inhibittyrosinase and angiotensin-converting enzyme activities and scavengefree radicals in vitro (Chen, S-J et al., Studies on the inhibitoryeffect of Graptopetalum paraguayense E. Walther extracts on theangiotensin converting enzyme. Food Chemistry 100:1032-1036, 2007;Chung, Y-C et al., Studies on the antioxidative activity ofGraptopetalum paraguayense E. Walther. Food Chemistry 91:419-424, 2005;and Huang, K-F et al., Studies on the inhibitory effect of Graptopetalumparaguayense E. Walther extracts on mushroom tyrosinase. Food Chemistry89:583-587, 2005.) It was found that the water and 50% ethanolic and 95%ethanolic stem extracts of GP has antioxidant activity, which wereassayed for inhibitory effects on the proliferation of a human HCC cellline (HepG2) (Chen, S J et al., In vitro antioxidant andantiproliferative activity of the stem extracts from Graptopetalumparaguayense. Am J Chin Med 36:369-383, 2008). An in vivo research studydemonstrated that the leaf extracts of GP inhibited microgliaactivation, oxidative stress, and iNOS expression to reduce ischemicbrain injury (Kao, T K et al., Graptopetalum paraguayense E. Waltherleaf extracts protect against brain injury in ischemic rats. Am J ChinMed 38:495-516, 2010.).

It was disclosed in U.S. Pat. No. 7,364,758 filed in 2004 by Hsu andgranted in 2008 that the ethanolic extract from Graptopetalum hadanti-liver fibrosis and anti-inflammatory effects in vivo and in vitro.Then, its continuation-in-part application, U.S. Pat. No. 7,588,776, wasfiled in 2008 and granted in 2009 indicating that the water-solublefraction of Graptopetalum was effective in treating a liver disease orcondition, such as inflammation, steatosis, and fibrosis.

SUMMARY OF THE INVENTION

The present invention relates to a new extract and its fraction, and newcompounds, which are isolated from a plant, particularly Graptopetalumsp. The invention also provides a new approach for treating a cancer,particularly Hepatocellular carcinoma (HCC), using the new extract orthe new compounds.

In one aspect, the invention provides an extract with anti-canceractivity, which is extracted with Dimethyl sulfoxide (DMSO) from a plantselected from the group consisting of Graptopetalum sp., Rhodiola sp.and Echeveria sp. It is unexpectedly found in the present invention thatthe DMSO extract has anti-cancer activity.

In one embodiment of the invention, the plant is Graptopetalumparaguayense or Rhodiola rosea. In one example of the invention, theextract is obtained by extracting the plant with 30% DMSO.

In another aspect, the invention provides a fraction containing richanti-cancer components from a plant selected from the group consistingof Graptopetalum sp., Rhodiola sp. and Echeveria sp, particularlyGraptopetalum paraguayense or Rhodiola rosea, which is prepared byextracting the plant with Dimethyl sulfoxide (DMSO), and then isolatingby chromatography to obtain a fraction called as HH-F3, which haseffects in causing cytotoxicity and down-regulating AURKA, AURKB, andF1110540 expression in cancer cells.

In one embodiment of the invention, a Sephadex LH-20 column was used asa chromatography column. According to the invention, the fractionaccording to the invention has high cytotoxicity effects and iseffective in down-regulating AURKA, AURKB, and FLJ10540 expression inHuh7 and HepG2 cells.

In the mechanistic study on the fraction HH-F3, it was found that thefraction HH-F3 induced HCC to undergo apoptosis. In other words, it wasindicated that the fraction HH-F3 has a therapeutic effect on cancercells, particularly HCC.

In a further aspect, the invention provides a compound, having astructure of formula I below,

wherein one of the Rs is H, or a prucyanidin (PC) unit; and the other isOH or a prodelphindine (PD) unit; n is a number ranging from 21 to 38;and PC unit:PD unit<1:20. The structure of prucyanidin (PC) unit is

and the structure of prodelphindine (PD) is

According to the invention, the compound of formula I can be isolatedfrom a plant selected from the group consisting of Graptopetalum sp.,Rhodiola sp. or Echeveria sp. In one embodiment of the invention, thecompound was purified from the fraction of Graptopetalum paraguayense orRhodiola rosea. It was found that the compound of formula I is rich in3,4,5-trihydroxy benzylic moieties, and has anti-cancer activities.

In yet another aspect, the invention provides a composition or apharmaceutical composition, comprising the extract, the fraction or thecompound of the invention, and a pharmaceutically acceptable carrier.Furthermore, the pharmaceutical composition has anti-cancer activity,which is effective in the prevention or treatment of a cancer, such asliver cancer particularly HCC.

In further yet aspect, the invention provides the use of the extract,the fraction or the compound of formula I of the invention inmanufacture of a medicament for treating a cancer, particularly HCC.

In still another aspect, the invention provides a method for preventingor treating a cancer, comprising administering to a subject in needthereof a therapeutically effective amount of the extract, the fractionor the compound of the invention. In one example of the invention, thecancer is HCC.

The foregoing summary, as well as the following detailed description ofthe will be better understood when read in conjunction with the appendeddrawings. For the purpose of illustrating the invention, there are shownin the drawings the embodiments which are presently preferred. It shouldbe understood, however, that the invention is not limited to theembodiments shown in the drawings.

In the drawings:

FIG. 1 provides a HPLC fingerprint of the fraction HH-F3 according tothe invention, wherein the chromatogram and the elution gradient curvewere marked as Line X and Line Y, respectively.

FIG. 2A shows the effects of the fraction HH-F3 according to theinvention in causing an increase of cytotoxicity in Huh7 cells ascompared with other extracts prepared from different solvents, whereinHuh7 cells were treated with GP extracts prepared from water, acetone,methanol, 100% ethanol, 70% ethanol, 50% ethanol, 100% DMSO, and 30%DMSO at the concentrations of 100, 150, 250, 500, 750, 1000, and 1500μg/mL for 72 hours, after which the cells were subjected to MTT assays.Of these extract preparations, the 30% DMSO GP extracts exhibited themost significant inhibition of cell viability in Huh7 cells at 72 hours.

FIG. 2B shows the effects of the fraction HH-F3 according to theinvention in causing an increase of cytotoxicity in Mahlavu cells ascompared with other extracts prepared from different solvents, whereinMahlavu cells were treated with GP extracts prepared from water,acetone, methanol, 100% ethanol, 70% ethanol, 50% ethanol, 100% DMSO,and 30% DMSO at the concentrations of 100, 150, 250, 500, 750, 1000, and1500 μg/mL for 72 hours, after which the cells were subjected to MTTassays. Of these extract preparations, the 30% DMSO GP extractsexhibited the most significant inhibition of cell viability in Mahlavucells at 72 hours.

FIG. 3A shows the effects of the fraction HH-F3 according to theinvention in decreasing degradation of several mitotic regulators duringinterphase and M phase in HSC-T6 cells wherein HSC-T6 cells were treatedwith the 30% DMSO GP extracts. The cell lysates were subjected toimmunoblot analysis with anti-FLJ10540 and anti-AURKB antibodies.

FIG. 3B shows the effects of the fraction HH-F3 according to theinvention in decreasing degradation of several mitotic regulators duringinterphase and M phase in HepG2 and Huh7 cells that were treated withvarious concentrations of the 30% DMSO GP extracts; the cell lysateswere subjected to immunoblot analysis with anti-FLJ10540, anti-AURKA,and anti-AURKB antibodies.

FIG. 3C shows the effects of the fraction HH-F3 according to theinvention in decreasing degradation of several mitotic regulators duringinterphase and M phase in HepG2 and Huh7 cells, wherein HepG2 and Huh7cells were treated with 75 ng/mL nocodazole (NOC) for 16-18 hours. Afterpretreatment with the synchronizing agent, the cells were then treatedwith 750 μg/mL 30% DMSO GP extracts or vehicle control (30% DMSO) foranother 3 hours; Western blots were performed using anti-F1110540,anti-AURKA, and anti-AURKB antibodies; it is important to note thefollowing: (1) AURKA, AURKB, and FLJ10540 were highly expressed inmitotic cells compared with interphase cells, and (2) the proteinexpression levels of AURKA, AURKB, and FLJ10540 in interphase andmetaphase were both suppressed after treatment with the 30% DMSO GPextracts.

FIG. 4A shows the effects of the fraction HH-F3 according to theinvention in suppressing AURKA protein expression in the HCC cell lines(Huh7 cells) wherein Huh7 cells were treated with GP extracts that wereprepared from water, acetone, methanol, 100% ethanol, 70% ethanol, 50%ethanol, 100% DMSO, 30% DMSO at a concentration of 500 μg/mL for 48hours; and AURKA expression levels were inhibited after treatment withthe 30% DMSO GP extracts.

FIG. 4B shows the effects of the fraction HH-F3 according to theinvention in suppressing AURKA protein expression in the HCC cell lines(HepG2 and Huh7 cells) wherein AURKA, AURKB, and F1110540 expressionlevels were not suppressed by the water and BuOH fractions in the HepG2and Huh7 cells.

FIG. 5A shows the time- and dose-dependent response in causingcytotoxicity of the fraction HH-F3 according to the invention in Huh7cells wherein Huh7 (FIG. 5A) cells were treated with the 30% DMSO GPextracts at concentrations of 0, 250, 500, 750, and 1000 μg/mL for 24,48, and 72 hours, followed by MTT assays. The IC₅₀ values for growthinhibition caused by the 30% DMSO GP extracts in Huh7 cells wereapproximately 500 μg/mL at 48 hours.

FIG. 5B shows the time- and dose-dependent response in causingcytotoxicity of the fraction HH-F3 according to the invention in Mahlavucells wherein Mahlavu cells were treated with the 30% DMSO GP extractsat concentrations of 0, 250, 500, 750, and 1000 μg/mL for 24, 48, and 72hours, followed by MTT assays. The IC₅₀ values for growth inhibitioncaused by the 30% DMSO GP extracts in Mahlavu cells were approximately250 μg/mL at 48 hours.

FIG. 6A shows the effects of the different purification fractions of GPon AURKA protein expression in the HCC cell lines, illustrating thepurification scheme of the GP extract and fraction HH-F3 according tothe invention.

FIG. 6B shows that HepG2 cells were treated with the 30% DMSO GPextracts, HH-F1, HH-F2, HH-F3, and HH-F4 for 3 hours. AURKA and AURKBexpression levels were not suppressed by treatment with the HH-F1, HH-F2and HH-F4 fractions in HepG2 cells.

FIG. 6C shows that the expression of AURKA was inhibited after treatmentwith the 30% DMSO GP extracts and the HH-F3 fraction.

FIG. 6D shows that the expression of AURKA was inhibited after treatmentwith the HH-F3a fraction.

FIG. 7A shows the effects of the fraction HH-F3 according to theinvention in inhibition of Huh7 cells, wherein Huh7 cells were treatedwith the HH-F3 fraction at concentrations of 5, 25, 50, and 75 μg/mL for24, 48, and 72 hours, followed by MTT assays. The IC₅₀ value for theinhibition of cell viability caused by treatment with the HH-F3 fractionin Huh7 cells was approximately 50 μg/mL after treatment for 72 hours.

FIG. 7B shows the effects of the fraction HH-F3 according to theinvention in inhibition of Mahlavu cells, wherein Mahlavu cells weretreated with the HH-F3 fraction at concentrations of 5, 25, 50, and 75μg/mL for 24, 48, and 72 hours, followed by MTT assays. The IC₅₀ valuefor the inhibition of cell viability caused by treatment with the HH-F3fraction in Mahlavu cells was approximately 37.5 μg/mL after treatmentfor 72 hours.

FIG. 7C shows the effects of the fraction HH-F3 according to theinvention in inhibition of PLC5 cells, wherein PLC5 cells were treatedwith the HH-F3 fraction at concentrations of 5, 25, 50, and 75 μg/mL for24, 48, and 72 hours, followed by MTT assays. The IC₅₀ value for theinhibition of cell viability caused by treatment with the HH-F3 fractionin PLC5 cells was approximately 75 μg/mL after treatment for 72 hours.

FIG. 7D shows the effects of the fraction HH-F3 according to theinvention in inhibition of HSC-T6 cells, wherein HSC-T6 cells weretreated with the HH-F3 fraction at concentrations of 5, 25, 50, and 75μg/mL for 24, 48, and 72 hours, followed by MTT assays. The IC₅₀ valuefor the inhibition of cell viability caused by treatment with the HH-F3fraction in HSC-T6 cells was approximately 20 μg/mL after treatment for72 hours.

FIG. 7E shows the effects of the fraction HH-F3 according to theinvention in inhibition of Huh7 cells, wherein Huh7 cells were treatedwith the HH-F3 fraction at concentrations of 5, 25, 50, and 75 μg/mL for24, 48, and 72 hours, followed by trypan blue assays.

FIG. 7F shows the effects of the fraction HH-F3 according to theinvention in inhibition of Mahlavu cells, wherein Mahlavu cells weretreated with the HH-F3 fraction at concentrations of 5, 25, 50, and 75μg/mL for 24, 48, and 72 hours, followed by trypan blue assays.

FIG. 7G shows the effects of the fraction HH-F3 according to theinvention in inhibition of PLC5 cells, wherein PLC5 cells were treatedwith the HH-F3 fraction at concentrations of 5, 25, 50, and 75 μg/mL for24, 48, and 72 hours, followed by trypan blue assays.

FIG. 8A shows that the HH-F3 fraction down-regulates AURKA and F1110540in HCC cell lines and activated hepatic stellate cells. In FIG. 8A,Huh7, Mahlavu, and PLC5 cells were treated with the HH-F3 fraction atconcentrations of 25, 50, or 75 μg/mL for 3 hours. Expression of bothAURKA and FLJ10540 was down-regulated in a concentration-dependentmanner, as examined by immunoblot analysis with anti-FLJ10540 andanti-AURKA antibodies.

FIG. 8B shows that the HH-F3 fraction down-regulates AURKA and F1110540in HCC cell lines and activated hepatic stellate cells. In FIG. 8B,HSC-T6 cells were treated with the HH-F3 fraction at concentrations of5, 15, and 50 μg/mL for 3 hours; FLJ10540 expression was down-regulatedin a concentration-dependent manner.

FIG. 9A shows the effect of the fraction HH-F3 in causing apoptosis inHHC cell lines; Huh7 cells were treated with 5, 25, and 50 μg/mL HH-F3for 24 and 48 hours. After treatment with the HH-F3 fraction for 24 and48 hours (FIG. 9B), the cell lysates were subjected to immunoblotanalysis for anti-cleaved caspase-3 and cleaved PARP. FIG. 9A shows theresults for Huh7 cells.

FIG. 9B shows the effect of the fraction HH-F3 in causing apoptosis inHHC cell lines; Mahlavu cells were treated with 5, 25, and 50 μg/mLHH-F3 for 24 and 48 hours. After treatment with the HH-F3 fraction for24 and 48 hours, the cell lysates were subjected to immunoblot analysisfor anti-cleaved caspase-3 and cleaved PARP. FIG. 9B shows the resultsfor Mahlavu cells.

FIG. 10A shows the effect of the fraction HH-F3 in decreasingmitochondrial membrane potential and increasing ROS generation in theHCC cell lines; mitochondria membrane potential (ΔΨ) of Huh7 cells wasanalyzed using the JC-1 mitochondrial membrane potential assay, and theAT of the cells decreased after treatment with the fraction HH-F3 at theconcentrations of 5, 10, 15, 25, and 50 μg/mL for 48 hours (n=2);RFU=AT.

FIG. 10B shows the effect of the fraction HH-F3 in decreasingmitochondrial membrane potential and increasing ROS generation in theHCC cell lines; mitochondria membrane potential (ΔΨ) of Mahlavu cellswas analyzed using the JC-1 mitochondrial membrane potential assay, andthe AT of the cells decreased after treatment with the fraction HH-F3 atthe concentrations of 5, 10, 15, 25, and 50 μg/mL for 48 hours (n=2);RFU=AT.

FIG. 10C shows the effect of the fraction HH-F3 in decreasingmitochondrial membrane potential and increasing ROS generation in theHCC cell lines for Huh7 cells; intracellular superoxide (O₂ ⁻) levels,as measured by hydroethidine (HE) staining, were decreased significantly48 hours after treatment with the fraction HH-F3 at the concentrationsof 5, 10, 15, 25, and 50 μg/mL as compared with the control HCC cells(Huh7 cells treated with DMSO).

FIG. 10D shows the effect of the fraction HH-F3 in decreasingmitochondrial membrane potential and increasing ROS generation in theHCC cell lines for Mahlavu cells; intracellular superoxide (O₂ ⁻)levels, as measured by hydroethidine (HE) staining, were decreasedsignificantly 48 hours after treatment with the fraction HH-F3 at theconcentrations of 5, 10, 15, 25, and 50 μg/mL as compared with thecontrol HCC cells (Mahlavu cells treated with DMSO).

FIG. 10E shows that intracellular peroxide levels, as measured by DCFH,were increased 48 hours after treatment with the fraction HH-F3 at theconcentrations of 5, 10, 15, 25, and 50 μg/mL for Huh7 cells as comparedwith control HCC cells (Huh7 treated with DMSO), and it was found thatthe production of intracellular peroxide and superoxide increased in adose-dependent manner in Huh7 cells after treatment with the fractionHH-F3.

FIG. 10F shows that intracellular peroxide levels, as measured by DCFH,were increased 48 hours after treatment with the fraction HH-F3 at theconcentrations of 5, 10, 15, 25, and 50 μg/mL for Mahlavu cells ascompared with control HCC cells (Huh7 treated with DMSO), and it wasfound that the production of intracellular peroxide and superoxideincreased in a dose-dependent manner in Mahlavu cells after treatmentwith the fraction HH-F3.

FIG. 11 shows the effect of the fraction HH-F3 in inhibiting AKT-Ser⁴⁷³phosphorylation and activating PTEN protein expression in Huh7 cellsthat were treated with the fraction HH-F3 at the concentrations of 25,50, or 75 μg/mL for 48 hours, and the expression of AURKA, FLJ10540,AKT-Ser⁴⁷³ was down-regulated, whereas PTEN was up-regulated in aconcentration-dependent manner, as examined by immunoblot analysis withanti-F1 LJ0540, anti-AURKA, anti-AKT-Ser⁴⁷³, and anti-PTEN antibodies.

FIG. 12A shows the effects of the GP extract and the fraction HH-F3according to the invention in decreasing the hydroxyproline content incirrhotic liver and tumor burdens; wherein the animals were divided intofour groups; they were provided with tap water only (normal group) orwith DEN solution (the other group), as described in the Materials andMethods. FIG. 12A shows the decreased bile flow in cirrhotic animals,which was recorded to measure liver function (*P<0.05; ANOVA).

FIG. 12B shows the effects of the GP extract and the fraction HH-F3according to the invention in decreasing the hydroxyproline content incirrhotic liver and tumor burdens; wherein the animals were divided intofour groups; they were provided with tap water only (normal group) orwith DEN solution (the other group), as described in the Materials andMethods. FIG. 12B shows the enlarged spleen size in cirrhotic animalswherein the spleen weights and body weights (BWs) were measured andexpressed as spleen weight/BW; the ratios of spleen weight/BW of the DENgroup was significantly higher than those of the normal group, whichindicates that the splenomegaly was due to cirrhosis-related portalhypertension (P<0.05, ANOVA), whereas only the ratio of spleen weight/BWof the high-dose group was significantly lower than those of the DENgroup (P<0.05, ANOVA).

FIG. 12C shows the effects of the GP extract and the fraction HH-F3according to the invention in decreasing the hydroxyproline content incirrhotic liver and tumor burdens; wherein the animals were divided intofour groups; they were provided with tap water only (normal group) orwith DEN solution (the other group), as described in the Materials andMethods. FIG. 12C shows the increased collagen content in cirrhoticlivers, wherein liver cirrhosis was determined by measuring the levelsof liver hydroxyproline content and significant decreases were observedwhen comparing the high-dose group, the HH-F3 group and the controlgroup.

FIG. 12D shows the effects of the GP extract and the fraction HH-F3according to the invention in decreasing the hydroxyproline content incirrhotic liver and tumor burdens; wherein the animals were divided intofour groups; they were provided with tap water only (normal group) orwith DEN solution (the other group), as described in the Materials andMethods. FIG. 12D shows the expression of α-SMA induced by DEN. Theformalin/paraffin sections of the liver samples from each group duringthe course of DEN feeding stained with an antibody against α-SMA, thepercentages of α-SMA (+) area were determined by a Digital Camera Systemusing the 10 fields with the densest staining (*P<0.05; **P<0.005,ANOVA).

FIG. 12E shows the effects of the GP extract and the fraction HH-F3according to the invention in decreasing the hydroxyproline content incirrhotic liver and tumor burdens; wherein the animals were divided intofour groups; they were provided with tap water only (normal group) orwith DEN solution (the other group), as described in the Materials andMethods. FIG. 12E shows the oxidative stress induced by DEN. NBT(Nitrotetrazolium blue chloride) is a dye that is reduced to aninsoluble blue-colored formazan derivative upon exposure to superoxide,and the blue-colored deposit as a histological marker for the presenceof superoxide in tissue is detectable by light microscopy, the densityof NBT (+) foci was determined, as described in the Materials andMethods, from the 10 fields with the densest staining.

FIG. 12F shows the effects of the GP extract and the fraction HH-F3according to the invention in decreasing the hydroxyproline content incirrhotic liver and tumor burdens; wherein the animals were divided intofour groups; they were provided with tap water only (normal group) orwith DEN solution (the other group), as described in the Materials andMethods. FIG. 12F shows the measurement of tumor burdens wherein thelivers obtained from the sacrificed animals were sliced into 5-mmsections, the numbers and sizes of all visible tumor nodules withdiameters larger than 3 mm were counted and measured. Tumor burdens areexpressed as the sum of the volume of total tumor nodules (**P<0.005,***P<0.001 as compared to the DEN group).

FIG. 12G shows the effects of the GP extract and the fraction HH-F3according to the invention in decreasing the hydroxyproline content incirrhotic liver and tumor burdens; wherein the animals were divided intofour groups; they were provided with tap water only (normal group) orwith DEN solution (the other group), as described in the Materials andMethods. FIG. 12G shows the gross picture of chemical-induced HCC andcirrhosis, wherein the 9 weeks of oral administration of DEN in drinkingwater on the rat livers resulted in multiple hepatic tumors in thecirrhotic rat livers, and the development of granulation on the surfaceand the uneven boundary with multiple hepatic tumors was observed inthese animals.

FIG. 13A shows the effect of the Rhodiola rosea extract in inhibitingthe cell viability of the HCC cell lines (PLC5, Huh7, and Mahlavu) anddown-regulating AURKA protein expression. FIG. 13A shows the effect ofthe extract on inhibiting the cell viability.

FIG. 13B shows the effect of the Rhodiola rosea extract in inhibitingthe cell viability of the HCC cell lines (PLC5, Huh7, and Mahlavu) anddown-regulating AURKA protein expression. FIG. 13B shows the effect onthe extract on AURKA expression, with β-actin as a control.

DETAILED DESCRIPTION

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by a person skilled in theart to which this invention belongs.

As used herein, the singular forms “a”, “an”, and “the” include pluralreferents unless the context clearly dictates otherwise. Thus, forexample, reference to “a sample” includes a plurality of such samplesand equivalents thereof known to those skilled in the art.

The invention provides a new extract of a plant selected from the groupconsisting of Graptopetalum sp., Rhodiola sp. or Echeveria sp., preparedby extracting the plant with DMSO, referred to as the GP extract. It isunexpectedly found in the present invention that the GP extract hasanti-cancer activity.

According to the invention, the extract may be prepared by extractingthe plant with dimethyl sulfoxide (DMSO) using commonly used or standardmethods in this art. In one example of the invention, the leaves of theplant are grounded and lyophilized into powder and vortexed with DMSO,preferably 30% DMSO. A further extraction with methanol (MeOH) may beincluded before the extraction with DMSO.

The term “Graptopetalum”, as used herein, refers to any plant in thegenus of Graptopetalum, or part or parts thereof. Combinations of morethan one species of Graptopetalum, or parts thereof, are alsocontemplated. The Graptopetalum is preferably Graptopetalumparaguayense.

The term “Rhodiola”, as used herein, refers to any plant in the genus ofRhodiola, or part or parts thereof. Combinations of more than onespecies of Rhodiola, or parts thereof, are also contemplated. TheRhodiola is preferably Rhodiola rosea.

The term “Echeveria”, as used herein, refers to any plant in the genusof Echeveria, or part or parts thereof. Combinations of more than onespecies of Echeveria, or parts thereof, are also contemplated. TheEcheveria is preferably Echeveria peacockii.

In one preferred embodiment of the invention, the plant is Graptopetalumparaguayense or Rhodiola rosea.

The term “extract” as used herein refers to a solution obtained bysoaking or mixing a substance to be extracted with a solvent. In thepresent invention, the extract is a DMSO extract.

The invention also provides a fraction containing rich anti-cancercomponents from a plant selected from the group consisting ofGraptopetalum sp., Rhodiola sp. and Echeveria sp, which is prepared byextracting the plant with Dimethyl sulfoxide (DMSO), and then isolatingby chromatography to obtain a fraction called as HH-F3. In one exampleof the invention, the plant is Graptopetalum paraguayense or Rhodiolarosea. The fraction is obtained by extracting the plant with DMSO andisolating by chromatography to obtain a fraction, referred to as HH-F3.In one example of the invention, a Sephadex LH-20 column is used forchromatography. It was found that the fraction has effects in causingcytotoxicity and down-regulating AURKA, AURKB, and F1110540 expressionin cancer cells, particularly the HCC cell lines such as Huh7 and HepG2cells. A mechanistic study of the fraction HH-F3 was performed and itwas indicated that the fraction HH-F3 induced HCC to undergo apoptosis.Accordingly, the fraction HH-F3 is a potential therapeutic agent for theprevention or treatment of a cancer, particularly liver cancer, such asHCC.

According to one example of the invention, a sub-fraction referred to asHH-F3a was obtained from the fraction HH-F3 via dialysis. Then, theactive compounds were isolated from the HH-F3a fraction, which isdifferent from the known proanthocyanidin compounds. The compound asobtained is a proanthocyanidin rich in 3,4,5-trihydroxy benzylicmoieties. The compound is of a structure of formula I below,

wherein one of the Rs is H, or a prucyanidin (PC) unit; and the other isOH or a prodelphindine (PD) unit; n is a number ranging from 21 to 38;and PC unit:PD unit<1:20. The structure of a prucyanidin (PC) unit is

and the structure of prodelphindine (PD) is

Accordingly, the invention provides the compound of formula I, which isproved to have anti-cancer activity. In one example to the invention,the compound of formula I was obtained by an extraction from the plantof Graptopetalum sp., Rhodiola sp. or Echeveria sp. with DMSO to obtaina DMSO extract, a selection from the DMSO extract using down-regulationregulation of AURKA via western blot to obtain a sub-fraction referredto as “HH-F3a” via dialysis, and a further purification.

The invention provides a pharmaceutical composition, comprising atherapeutically effective amount of the extract, the fraction or thecompound of formula I of the invention, and a pharmaceuticallyacceptable carrier.

The term “therapeutically effective amount” as used herein refers to anamount of an agent sufficient to achieve the intended purpose fortreatment. For example, an effective amount of Graptopetalum to treatHCC is an amount sufficient to kill HCC cells. The therapeuticallyeffective amount of a given agent will vary with factors such as thenature of the agent, the route of administration, the size and speciesof the animal to receive the agent, and the purpose of theadministration. The therapeutically effective amount in each individualcase may be determined empirically by a skilled artisan according to thedisclosure herein and established methods in the art. The pharmaceuticalcomposition of the invention may be administered in any route that isappropriate, including but not limited to parenteral or oraladministration. The pharmaceutical compositions for parenteraladministration include solutions, suspensions, emulsions, and solidinjectable compositions that are dissolved or suspended in a solventimmediately before use. The injections may be prepared by dissolving,suspending or emulsifying one or more of the active ingredients in adiluent. Examples of said diluents are distilled water for injection,physiological saline, vegetable oil, alcohol, and a combination thereof.Further, the injections may contain stabilizers, solubilizers,suspending agents, emulsifiers, soothing agents, buffers, preservatives,etc. The injections are sterilized in the final formulation step orprepared by sterile procedure. The pharmaceutical composition of theinvention may also be formulated into a sterile solid preparation, forexample, by freeze-drying, and may be used after sterilized or dissolvedin sterile injectable water or other sterile diluent(s) immediatelybefore use.

According to the invention, the composition may also be administeredthrough oral tablets, pills, capsules, dispersible powders, granules,and the like. The oral compositions also include gargles which are to bestuck to oral cavity and sublingual tablets. The capsules include hardcapsules and soft capsules. In such solid compositions for oral use, oneor more of the active compound(s) may be admixed solely or withdiluents, binders, disintegrators, lubricants, stabilizers,solubilizers, and then formulated into a preparation in a conventionalmanner. When necessary, such preparations may be coated with a coatingagent, or they may be coated with two or more coating layers. On theother hand, the liquid compositions for oral administration includepharmaceutically acceptable aqueous solutions, suspensions, emulsions,syrups, elixirs, and the like. In such compositions, one or more of theactive compound(s) may be dissolved, suspended or emulsified in acommonly used diluent (such as purified water, ethanol or a mixturethereof, etc.). Besides such diluents, said compositions may alsocontain wetting agents, suspending agents, emulsifiers, sweeteningagents, flavoring agents, perfumes, preservatives and buffers and thelike.

It was confirmed in the examples that the extract, the fraction or thecompound of the invention, or the pharmaceutical composition thereofcaused an apoptosis in HCC cells, suggesting that they have anti-canceractivity, which may be used for the prevention or treatment of a cancer,particularly HCC. On the other hand, it is suggested that they areeffective in treatment of fibrosis, particularly liver fibrosis.

Accordingly, the invention provides the use of the extract, the fractionor the compound of formula I of the invention in manufacture of amedicament for treating a cancer, particularly, HCC. On the other hand,the invention provides a method for preventing or treating a cancer orfibrosis comprising administering to a subject in need thereof atherapeutically effective amount of the extract, the fraction or thecompound of the invention, particularly HCC and liver fibrosis.

The following examples are offered to illustrate this invention and arenot to be construed in any way as limiting the scope of the presentinvention.

EXAMPLE Example 1 Extraction and Purification from GP or Rhodiola rosea

The leaves of Graptopetalum paraguayense (referred to as GP) were groundand lyophilized into powder at −20° C. and stored in a moisture busterat 25° C. before extraction. First, 1.5 g GP powder was vortexed with 10mL 100% methanol (MeOH) for 5 minutes and then centrifuged at 1500 g for5 minutes. After removal of the supernatant, 10 mL H₂O, 100% acetone,100% methanol, 100% ethanol, 70% ethanol, 50% ethanol, 100% DMSO and 30%DMSO was added to each pellet to resuspend them for each extract. Thesuspension was mixed by vortexing for 5 minutes, centrifuged twice at1500 g for 5 minutes, centrifuged again at 9300 g for 5 minutes, andfiltered using a 0.45 μm filter by laminar flow at room temperature. The30% DMSO supernatant was either fractionated into four fractions (FI-F4)by a Sephadex LH-20 20 column or stored at −20° C. as a 150 mg/mL stocksolution (referred to as 30% DMSO GP extracts). The GP extract or thefraction HH-F3 was also subjected to dialysis against water by adialysis membrane (MWCO 12-14,000) (Spectrum Laboratories, RanchoDominguez, Calif.) to obtain active compounds. Using the analysis ofAURKA, AURKB, and FLJ10540 protein levels via Western blot, activemolecules were analyzed, which we refer to as the fraction HH-F3. Inaddition, the fraction HH-F3 was further analyzed by HPLC and ¹H- and¹³C-NMR spectra to identify the structure of the active molecules.

Similarly, the plants of Rhodiola rosea (referred to as RS) werelyophilized into powder and stored in moisture buster at 25° C. beforeextraction. One and a half grams of RS powder was dissolved in 10 mL H₂Oand then centrifuged at 1500 g for 5 minutes, followed by filteringusing a 0.45 μm filter by laminar flow at room temperature. The sampleswere stored at −20° C. as 150 mg/mL stock solutions.

A chemical investigation on the fraction HH-F3 of the invention resultedin the identification of its major components as polyphenolic compounds,according to broadened aromatic signals in the ¹H and ¹³C NMR spectra.The major compounds in the HH-F3 fraction were identified to be tanninsbecause of their characteristic pink color with partial silvermetal-like like luster after lyophilization. The total tannin content ofthe HH-F3 fraction was approximately 68%, as determined by acolorimetric assay for condensed tannin quantification, which usedcatechin as the standard when monitored at OD₅₀₀. The HPLC fingerprintof the HH-F3 fraction (FIG. 1) revealed that two groups of compounds(Groups A and B) with distinct molecular weight ranges existed in theHH-F3 fraction, and one major and one minor component were detected inGroup B. A proanthocyanidin-rich high molecular weight fraction, HH-F3a(with a yield of 71.9% compared to the amount of the starting materialHH-F3), was prepared from the HH-F3 fraction using dialysis. Briefly,HH-F3 (112.1 mg) was dialyzed by a dialysis membrane (MWCO 12-14,000)against water to give an inner membrane fraction (HH-F3A, 80.6 mg) andan outer-membrane fraction (7.4 mg). This fraction contained the activecompounds, as determined by measuring the disappearance of AURKA byWestern blot (FIG. 6D). The main skeleton for the proanthocyanidinfraction of HH-F3a was determined to be a proanthocyanidin polymer (seebelow), and its physiochemical properties, including the mean molecularweight (mMW), mean degree of polymerization (mDP), PC:PD ratio andstereochemistry (cis:trans), are listed in Table 1. mMW and mDP weredetermined by analyzing the ratio of the degraded terminal andelongating monomers. In addition, to simplify the preparation protocols,another method via directly dialysis of GP extracts against water(Method II) was performed, and the physiochemical data of the compoundsprepared by Method II are also listed in Table 1. The listedphysiochemical properties in Table 1 suggest that the fraction preparedby Method II was identical to that of Method I (the method used toprepare HH-F3a).

TABLE 1 Physicochemical Properties for the Proanthocyanidin Polymer ofFormula 1 According to the Invention mMW Preparation PC:PD Cis:trans3-O-galloyl mDP (kD) Method I <1:20 2,3-cis >95% 40 18 3,4-trans MethodII <1:20 2,3-cis >95% 40 18 3,4-trans ¹ The method that prepared HH-F3a(by Sephadex LH-20 chromatography) ² by dialysis

Since no polymeric compound from GP has been reported, the polyphenoliccompounds from another precious crassulaceous herb Rhodiola rosea(golden root) are utilized as reference compounds for structuralidentification of HH-F3a. R. rosea has been reported to have polymericproanthocyanidin (PAC). The structure of the main compounds in theHH-F3a fraction was very similar to the proanthocyanidin compounds of R.rosea (see Table 2) but with rather minor signals (<5%) for aprocyanidin unit (PC unit), which was not detectable in the ¹³C NMRspectrum (δ_(C) 114 ppm, B ring C-2′ and C-5′). In addition, the PACcompounds are frequently found in many common grape species, such asVitis vinifera. Thus, the PACs from V. vinifera are also brought intocomparison. Table 2 shows the physiochemical properties for theproanthocyanidin polymers from R. rosea and V. vinifera (a common grapespecies). Compared to the data in Table 2, the proanthocyanidin compoundin the HH-F3a fraction was within 2.5× of the PD to PC ratio, 3.0× ofthe mDP and mMW for R. rosea, and 30 to 80×, 1.1 to 4.9×, and 4.7 to41.3× higher than the mDP, mMW and % of 3-O-galloyl for V. vinifera. Tothe best of our knowledge, no proanthocyanidin compound from GP has beenisolated, and no proanthocyanidin compound with identical physiochemicalproperties has been reported. This evidence suggests that theproanthocyanidin compound found in the HH-F3a fraction is a new compoundthat is rich in 3,4,5-trihydroxy benzylic moieties (including a B ringof the PD unit and gallic acid), very similar to that found in R. roseabut much higher than that found in grape skin and seed.

TABLE 2 Physicochemical Properties for Known Proanthocyanidin Polymers3-O-galloyl mMW Source PC:PD cis:trans (%) mDP (kD) Rhodiola rosea 1:82,3-cis >95 13.3 6.0 3,4-trans Seed of 4:1 2,3-cis 20.4 8.1 2.6 Vitisvinifera ¹ Skin of 3:2 2,3-cis 2.3 34.9 10.4 Vitis vinifera ¹TheEuropean grapevine native to the Mediterranean and Central Asia

Example 3 Effect Examples

1. Viability Assay

The cells were seeded in 24-well plates (4,000-5,000 cells/well),incubated overnight and then treated with the 30% DMSO GP extract or theHH-F3 fraction for 0, 24, 48, or 72 hours. After treatment, the cellswere gently washed 3 times with 1×PBS (137 mM NaCl, 2.7 mM KCl, 10 mMNa₂HPO₄, 2 mM KH₂PO₄) and then were incubated with 0.5 μg/mL3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) for2 hours. The medium was removed, and the deep-blue crystals weredissolved with 100% DMSO at room temperature for 10 minutes. OD valueswere measured at 570 nm with an ELISA reader.

2. Western Blot

All samples were denatured by heating at 95° C. for 10 minutes andresolved by 8% or 10% SDS-polyacrylamide gel electrophoresis (SDS-PAGE)at 80 V and 100 V for the stacking and running gel, respectively. AfterSDS-PAGE, the proteins were transferred to polyvinylidene difluoride(PVDF) membranes using the Bio-Rad transfer system. After the proteinswere transferred, the membranes were stained with Ponceau S to confirmthe efficiency and uniformity of the protein transfer. The membraneswere blocked with 5% non-fat skim milk (BD) at room temperature for 30minutes and then were incubated with primary antibody at 4° C.overnight. Afterward, the membranes were washed with 1× Tris-bufferedsaline Tween-20 (TBST) three times (10 minutes each). The membranes wereincubated with secondary antibody for 2 hours. Then, they were washedwith 1×TBST three times (10 minutes each). The signals of the secondaryantibodies were visualized by adding HRP substrate peroxidesolution/luminol reagents (Immobilon™ Western ChemiluminescentSubstrate, Millipore; mixed at a 1:1 ratio) and were detected by theFujifilm LAS4000 luminescent image analysis system.

3. Cell Counting

The cells were seeded in 12-well plates (10,000-30,000 cells/well)overnight and then were treated with the HH-F3 fraction for 0, 24, 48,or 72 hours. The cells were trypsinized and then counted after mixingwith 0.4% trypan blue

4. Cell Cycle Analysis and Flow Cytometry

After trypsinizing the cells and washing with 1×PBS 3 times, the cellswere centrifuged at 800 g for 5 minutes. Then, the cells wereresuspended in 70% ethanol in PBS and kept at −20° C. for more than 16hours. After centrifugation at 800 g for 5 minutes, the cell pelletswere resuspended with cold PBS containing 100 μg/mL RNAse A(Sigma-Aldrich) for 20 minutes. Then, the cells were stained with 20μg/mL propidium iodide (PI, Sigma-Aldrich) for 20-30 minutes, and theDNA content was measured by the BD FACSCanto and analyzed by FlowJosoftware.

5. Mitochondrial Membrane Potential Assay

Mitochondrial membrane potential was analyzed using5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethylbenzimidazolcarbocyanineiodide (JC-1), which was purchased from Cayman Chemical Co. The culturedcells were seeded in 96-well black plates at a density of 7000cells/well and incubated overnight, then treated with or without theHH-F3 fraction for 48 hours. The JC-1 staining solution was added toeach well and mixed gently at 37° C. for 15-30 minutes in the dark. Theplates were centrifuged at 400 g at room temperature for 5 minutes, andthe supernatant was removed. Then, JC-1 assay buffer was added to eachwell, followed by centrifugation at 400 g at room temperature for 5minutes, after which the supernatant was removed. Finally, JC-1 assaybuffer was added to each well for analysis using a fluorescent platereader.

6. Measurement of ROS Levels

Intracellular generation of superoxide radicals (O₂ ⁻) was assessed byhydroethidine fluorescence (AAT Bioquest, Inc.). The cells were treatedwith or without the HH-F3 fraction for 48 hours. Hydroethidine (10 μM)was added to each well and was mixed gently for 30-60 minutes at 37° C.in the dark. Cellular fluorescence was monitored at wavelengths of 520nm (excitation) and 610 nm (emission).

Intracellular peroxide levels were determined with dichlorofluorescein(DCFH) diacetate (Marker Gene Technologies, Inc.). Following treatmentwith the HH-F3 fraction for 48 hours, the medium was aspirated, and thecells were washed twice with PBS. Then, the cells were incubated withDCFH at a final concentration of 20 tM in serum-free media for 30-60 minat 37° C. in the dark. The cells were washed again with PBS andmaintained in 200 μL of culture media. Cellular fluorescence wasmonitored at wavelengths of 485 nm (excitation) and 528 nm (emission).

7. Animals and the Experimental Environment

A total of 120 male Wistar albino rats (150-180 g) that 6 weeks of ageat the start of the experimental period were used. All animals were fedad libitum with standard chow and water during the study and wereacclimated for 7 days before disease induction.

Experimental Protocol

The rats were randomly divided into the normal group (N=10), thediethylnitrosamine (DEN) group (N=30), the low-dose GP group (N=30) andthe high-dose GP group (N=30). We included another 5 rats for theHH-F3-treated group. In all groups except the normal group, the ratsdrank an aqueous solution of 100 ppm (v/v) DEN (Sigma-Aldrich, St.Louis, Mo., USA) daily as the sole source of drinking water for 63 days,and starting on day 64, they were fed tap water for another 14 days. DENsolution was prepared each week and consisted of an individualized doseaccording to the weight gain/loss of the animal in response to theprevious dose. Visible liver tumors were noted after day 42, and liverfibrosis was observed after day 63. During the experimental period, theanimals were weighed weekly to calculate weight gain, and the amount ofwater consumption was also measured every week. In the low-dose group,the rats received 0.6 g/rat lyophilized GP powder, and in the high-dosegroup, the rats received 1.8 g/rat lyophilized GP powder daily beginningon day 42 for 3 weeks.

Harvesting Procedure and Morphologic Evaluation of the Liver

All animals were euthanized on the day 84. The animals were fastedovernight and then sacrificed by CO₂ inhalation. After the rats weresacrificed, the bodies, livers and spleens were weighed, and theconditions of the organs were recorded after necropsy, which followed amidline laparotomy. All lobes of the liver were promptly harvested andthoroughly examined to clarify the nature of the liver surface and thedevelopment of liver foci, persistent nodules (PNs), or cancer at everytime point; subsequently, the liver was cut into 5-mm sections. Allmacroscopically visible nodules were counted on the liver surface and inthe 5-mm sections to determine their number and size.

Tumor Burden Assessment

To establish the course of tumor development in the animals fed withDEN, all lobes of the liver were promptly harvested, and allmacroscopically visible nodules were counted on the liver surface and inthe 5 mm sliced sections to determine their numbers and sizes. Tumorburdens were determined by estimating the sums of the volumes of alltumor nodules with diameters greater than 3 mm for each animal and thencomparing the groups.

Bile Flow Rate

Bile flow rate was measured prior to the sacrifice of the animals afterdeep anesthesia with 80 mg/kg ketamine. To measure the bile flow rate, aPE10 silicon tube was placed in the common bile duct and then connectedwith a calculated polyethylene tube. Bile flow in the tube was measuredat 5-min intervals.

Histopathological Evaluation

After draining the blood, tissue slices of approximately 5-mm thicknessthat contained tumors were dissected from each lobe of the liver.Sections with thicknesses of 5 μm were cut and stained with hematoxylinand eosin for histopathological analysis using published diagnosticcriteria.

Immunohistochemical Staining for α-Smooth Muscle Actin (α-SMA)

The liver samples were fixed with formalin, embedded with paraffin, andthen sectioned into 5 μm sections. The sections were deparaffinized,rehydrated and then treated with 0.03% hydrogen peroxide for 10 minutesto quench endogenous peroxidase activity. Following two washes with PBS,the sections were incubated for 1 h at room temperature with a mouseanti-human α-SMA monoclonal antibody (1:50 dilution, DakoCytomation,Denmark). For α-SMA staining, the sections were washed and furtherincubated with a secondary antibody, rabbit anti-mouse IgG (1:200dilution), at room temperature for 1 hour. The sections were thendeveloped similarly. After staining, the sections were counterstainedwith hematoxylin for microscopic examination. The percentage ofα-SMA-positive area (mm²/cm² of liver section) was measured using theDigital Camera System HC-2500 (Fuji Photo Film), Adobe Photoshop version5.0J, and Image-Pro Plus version 3.0.1J.

Assay of Hydroxyproline Content in the Liver

Liver specimens were weighed, and 20 mg of the frozen samples washydrolyzed in 20 mL of 6 N HCl and carefully ground. Additionally, 6 NHCl was then added to obtain a total volume of 30 mL per mg tissue. Theground tissue in HCl was hydrolyzed at 120° C. for 16 h. After briefcooling on ice and centrifugation at 8000 g for 10 min, the supernatantwas removed and placed in a new tube; the volume lost to evaporation wasreplenished by water. An equal volume of 6 N NaOH was added and mixed,and the solution was adjusted to pH 4-9 using litmus paper. Fortymicroliters of the neutralized sample solution was added to the wells ofa 96-well ELISA plate and oxidized using a solution containing 5 mL of7% chloramine T (Sigma-Aldrich) and 20 mL of acetate/citrate buffer.Thereafter, 150 mL of Ehrlich's solution was added. The final mixturewas incubated at 60° C. for 35 min and then at room temperature foranother 10 min, after which the absorbance was determined at 560 nm.Standard solutions containing 100, 80, 60, 40, 20 and 0 mg/mL ofauthentic 4-hydroxy-L-proline (Sigma-Aldrich) were treated likewise. Thestandard curve was linear in this range (r=0.99). The value of the liverhydroxyproline level was expressed as hydroxyproline (mg)/wet liverweight (g). All assays were repeated in triplicate.

Immunocytochemistry for Oxidative Stress

A nitroblue tetrazolium (NBT, Sigma-Aldrich) perfusion method was usedfor localizing de novo ROS generation in the liver. NBT-perfused liverswere removed and fixed in a zinc/formalin solution and processed forhistological examination of formazan deposits. The density of blue NBTdeposits was determined using Adobe Photoshop 7.0.1 image softwareanalysis.

Results

The Effects of Different GP Preparations on Huh7 and Mahlavu Cells

To test the potential biological effects of GP, different preparationsof GP extracts, including water extract, butanol extract, acetoneextract, methanol extract, 100% ethanol extract, 70% ethanol extract,50% ethanol extract, 100% DMSO extract and 30% DMSO extract wereprepared and used to treat human HCC cells. As shown in FIG. 1, thegrowth inhibitory effects that were caused by different preparations ofthe GP extracts were evaluated in a dose-dependent manner. The MTT assayresults indicated that the 30% DMSO extracts significantly inhibited theviability of Huh7 (FIG. 2A) and Mahlavu (FIG. 2B) cells.

The GP reduced AURKA, AURKB and FLJ10540 protein expression levelsduring both interphase and mitosis in activated hepatic stellate cellsand HCC cell lines.

AURKA, AURKB and FLJ10540 are oncogenes and are overexpressed in HCC.Therefore, we tested whether the different preparations of GP extractsinhibit these oncoproteins in human HCC cell lines. We found that the GPextracts (obtained from 100% methanol followed by 30% DMSO extraction,as described in the methods section and referred to as 30% DMSO GPextracts) inhibited the protein expression levels of FLJ10540 and AURKBin activated hepatic stellate cells (HSC-T6) (FIG. 3A) and suppressedthe protein expression levels of FLJ10540, AURKA, and AURKB in HCC cells(HepG2 and Huh7) (FIG. 3B). The expression levels of both AURKA andFLJ10540 are higher during metaphase than interphase. We nextinvestigated whether GP inhibits the expression of these two proteinsduring mitosis in HCC cells. Huh7 and HepG2 cells were treated with50-75 ng/mL nocodazole for 18 hours, followed by treatment with the 30%DMSO GP extracts for 3 hours without washing out the nocodazole.Consistent with previous findings, AURKA, AURKB, and FLJ10540 werehighly expressed during mitosis. The protein expression levels of AURKA,AURKB, and FLJ10540 were decreased during both interphase and metaphase(FIG. 3C), whereas no significant changes were observed in the othermitotic proteins that we examined, including PINT, HURP, and PLK (datanot shown).

The 30% DMSO GP extracts (the fraction HH-F3), but not the otherextracts that were prepared from different solvent, suppressed AURKAprotein expression in HCC cell lines.

Human HCC Huh7 cells were treated with 500 μg/mL of the differentpreparations of GP extracts for 48 hours. The 30% DMSO extractsignificantly inhibited the protein expression levels of AURKA in thesecells (FIG. 4A). In contrast, the GP extracts obtained from either wateror butanol did not inhibit the protein expression levels of AURKA orAURKB in HepG2 cells after 3 hours of treatment (FIG. 4B). Because AURKAand FLJ10540 are overexpressed in HCC, we examined whether GP has aneffect on the growth of HCC cells. We found that the 30% DMSO GPextracts caused cytotoxicity of Huh7 and Mahlavu cells with a 50%inhibitory concentration of cell viability (IC₅₀), which was determinedto be approximately 500 and 250 μg/mL at 48 hours post-treatment,respectively (FIG. 5).

HH-F3 Suppressed AURKA Protein Expression in HCC Cell Lines

The 30% DMSO GP extracts reduced the protein expression levels of AURKAand F1110540 in activated hepatic stellate cells and hepatoma cells(FIG. 2), suggesting that we could use this assay to purify the activemolecule(s) in GP. Using a Sephadex LH-20 column, we obtained fourfractions from the 30% DMSO GP extracts (FIG. 6A). Only the thirdfraction (referred to as HH-F3) suppressed the expression of AURKA andAURKB in HepG2 cells, as examined by Western blot at 3 hourspost-treatment, while the other fractions (HH-F1, HH-F2 and HH-F4) didnot inhibit AURKA and AURKB protein expression (FIG. 6B). Takentogether, GP extracts prepared from 30% DMSO and the HH-F3 fractioninhibited the protein expression levels of AURKA and AURKB in HepG2cells at 3 hours post-treatment (FIGS. 6B and 6C). We further obtainedan active subfraction from HH-F3, which is referred to as HH-F3a (with ayield of 71.9% compared to the amount of the starting material HH-F3),using dialysis. This HH-F3a fraction, but not HH-F3b fraction, containedthe active compounds, as determined by measuring the disappearance ofAURKA by Western blot (FIG. 6D).

The HH-F3 Fraction Reduces Cell Viability in HSC-T6 Cells and HCC CellLines

To investigate the effects of the HH-F3 fraction on cell viability,Huh7, Mahlavu, PLC5, and HSC-T6 cells were treated with the HH-F3fraction at concentrations of 5, 25, 50, 75, and 100 μg/mL for 24, 48,and 72 hours. The survival of these tested cell types were inhibited inresponse to HH-F3 treatment, as examined by the MTT assay. The IC₅₀values for treatment with the HH-F3 fraction in Huh7, Mahlavu, PLC5, andHSC-T6 cells at 72 hours were approximately 50, 37.5, 75, and 20 μg/mL,respectively (FIGS. 7A-7D). To further confirm this finding, cellsurvival was determined by trypan blue staining of Huh7, Mahlavu, andPLC5 cells. Decreases in cell survival after treatment with the HH-F3fraction were demonstrated in a time- and dose-dependent manner after24, 48, and 72 hours at concentrations of 5, 25, 50, 75, and 100 μg/mL(FIG. 7E-7G). Taken together, both the 30% DMSO GP extracts and theHH-F3 fraction can inhibit the cell viability of HCC cell lines andactivated hepatic stellate cells.

Next, Huh7, Mahlavu, PLC5, and HSC-T6 cells were treated with 25, 50,and 75 μg/mL of the HH-F3 fraction for 3 hours. The HH-F3 fractionsuppressed the expression of both AURKA and FLJ10540 in all three testedHCC cell lines and HSC-T6 cells (FIGS. 8A and 8B). To investigatewhether the inhibitory effects of the HH-F3 fraction occurred at thetranscriptional level, we examined the variation in the gene expressionlevels of FLJ10540 and the Aurora kinase family (AURKA, AURKB, andAURKC). HepG2 cells were treated with 50 μg/mL of the HH-F3 fraction for6 hours, after which gene expression levels were analyzed by microarray(U133A chip, Affymetrix), and protein levels were analyzed by Westernblot. Compared with the control group, there was no change in the geneexpression levels of the specific genes mentioned above after treatmentwith the HH-F3 fraction (data not shown), despite a decrease in proteinlevels. Therefore, the HH-F3 fraction probably regulates HCC cell growthat the protein level and not at the transcriptional level.

The HH-F3 Fraction Leads to Cell Death Via Apoptosis in HCC Cell Lines

The extracts were analyzed for the effects of the HH-F3 fraction on thecell cycle profiles of HCC cells using propidium iodide (PI) stainingHuh7 and Mahlavu cells were treated with 5, 25, and 50 μg/mL HH-F3 for48 hours. The HH-F3 fraction disturbed the cell cycle progression ofHuh7 and Mahlavu cells. After 48 hours of treatment with 50 μg/mL of theHH-F3 fraction, the sub-G1 population of Huh7 was 22%, while it was 26%in Mahlavu cells. The HH-F3 fraction generated a larger increase in thesub-G1 population in Mahlavu cells than in Huh7 cells, which is inaccordance with the cytotoxic effects demonstrated earlier (data notshown). We next examined the ability of the HH-F3 fraction to induceapoptotic cell death in Huh7 and Mahlavu cells. The protein expressionlevels of cleaved caspase-3 and cleaved PARP were increased in adose-dependent manner at concentrations of 5, 25, and 50 μg/mL for 24and 48 hours. Under the same concentration, HH-F3 fraction also resultedin the up-regulation of apoptotic molecule FAS and the down-regulationof BCL2 and BCL-XL (data not shown). These data indicate that the HH-F3fraction induces caspase-dependent apoptotic cell death (FIGS. 9A and9B).

The HH-F3 Fraction Decreases Mitochondrial Membrane Potential andIncreases ROS in HCC Cell Lines

Reactive oxygen species (ROS) and mitochondria play an important role inapoptosis induction under both physiological and pathologicalconditions. We next investigated whether the HH-F3 fraction triggersapoptosis via the extrinsic or intrinsic pathway. We tested whethermitochondrial membrane potential, one of the indicators of the intrinsicpathway, might be altered in HCC cells. Huh7 and Mahlavu cells weretreated with 5, 25, and 50 μg/mL of the HH-F3 fraction, and themitochondrial membrane potential of the cells was examined after 48hours of treatment. Compared to the control group, the number ofapoptotic cells was increased. This is in agreement with mitochondrialmembrane potential (AT) results, which show that the membrane potentialswere decreased in Huh7 and Mahlavu cells after treatment with the HH-F3fraction (FIG. 10A).

Several reports have shown that ROS are generated only after the loss ofΔΨW. ROS include superoxide anions, hydrogen peroxide, and hydroxylradicals, all of which are derived from oxygen. ROS are produced as aconsequence of electron transport processes during photosynthesis andaerobic respiration. ROS, at the physiological concentrations requiredfor normal cellular function, are involved in intracellular signalingand redox regulation. Excessive levels of ROS cause oxidative stress,which is potentially harmful to cells because it causes the oxidation oflipids, proteins and DNA. We tested whether stimulation of the HCC cellswith the HH-F3 fraction would result in changes in the production ofROS. Intracellular generation of O₂ ⁻ was assessed by hydroethidinefluorescence, and the level of intracellular peroxide was determinedwith DCFH diacetate. After the cells were treated with the HH-F3fraction, cellular production of intracellular peroxide (FIGS. 10C and10D) and superoxide (FIGS. 10E and 10F) were increased in HCC cells.This suggests that the HH-F3 fraction causes apoptosis via the intrinsicpathway.

The HH-F3 fraction decreased the phosphorylation of Akt and enhances theexpression of PTEN

Some cell proliferation pathways are related to apoptosis inhibition andabnormality in HCC, for example AKT pathway. Because HH-F3 caused cellcytotoxicity on HCC cells, we then investigated whether HH-F3 affectedthe cell proliferation pathways on HCC cells. The Huh7 cells weretreated with HH-F3 at 5, 25, 50 μg/mL for 48 hours, respectively. InHuh7 cells, the Ser⁴⁷³ phosphorylation of AKT was down-regulated underHH-F3 treatment, whereas the total AKT protein was not influenced (FIG.11). Interestingly, HH-F3 activated the protein level of phosphatase andtensin homolog (PTEN), which is a negative regulator of PI3K/AKTdependent signaling. These results indicated that HH-F3 may modulate AKTsignaling transduction pathway of cell proliferation to induce cellapoptosis.

GP Extracts Increased Bile Excretion Function of Cirrhotic Animals

Liver cirrhosis was also evaluated by measuring bile flow rates,reflecting liver function (FIG. 12A), by quantifying the ratios ofspleen weight/body weight, an indicator due to cirrhosis-related portalhypertension (FIG. 12B), and by analyzing the expression of α-SMAinduced by DEN (FIG. 12D). All of the data demonstrated that the statusof liver cirrhosis was improved after treated by high-dose GP, andpresented as increasing bile flow, decreased spleen size and decreasedthe percentages of α-SMA (+) area significantly.

GP Extracts and HH-F3 Decrease the Hydroxyproline Content in CirrhoticLiver

Liver fibrosis was determined by measuring the levels of liverhydroxyproline content. Significant increases of hydroxyproline levelwere observed in DEN-induced animals (143±30 μg/g). In contrast,following treatment with low dose GP, high dose GP or HH-F3, thehydroxyproline contents were 98±18 μg/g (P<0.05 compared with the DENgroup), 70±10 μg/g (P<0.05), and 72±8.2 μg/g (P<0.05), respectively(FIG. 12C).

GP Extracts and HH-F3 Decreased Oxidative Stress

NBT (Nitrotetrazolium blue chloride) is a dye that is reduced to aninsoluble blue-colored formazan derivative upon exposure to superoxide,and the blue-colored deposit as a histological marker for the presenceof superoxide in tissue is detectable by light microscopy. The densityof NBT (+) foci was determined from the 10 fields with the denseststaining Significant increases of NBT (+) foci were observed inDEN-induced animals (23±3). In contrast, following treatment with lowdose GP, high dose GP or HH-F3, the density of NBT (+)foci were 13±4(P<0.05 compared with the DEN group), 4.2±0.6 (P<0.005), and 6.2±2.1(P<0.05), respectively (FIG. 12E). These findings suggest that theoxidative stress induced by DEN could be reduced by the treatment of GPextracts and HH-F3.

GP Extracts and HH-F3 Decreased the Tumor Burdens

The livers obtained from the sacrificed animals were sliced into 5-mmsections. The numbers and sizes of all visible tumor nodules withdiameters larger than 3 mm were counted and measured. Tumor burdens areexpressed as the sum of the volume of total tumor nodules. Visibletumors were observed in DEN-induced animals (tumor burden 2350±905 mm³.In contrast, following treatment with low dose GP, high dose GP orHH-F3, the tumor burden in liver were 110±105 mm³ (P<0.005 compared withthe DEN group), 23±31 mm³ (P<0.005), and 86±12 (P<0.05), respectively(FIG. 12F). Representative photographs of the livers showed multiplehepatic tumors in the cirrhotic rat livers. The development ofgranulation on the surface and the uneven boundary with multiple hepatictumors was observed in these animals, and the visible tumor number anduneven liver surface were improved after treatment of low dose GP, highdose GP or HH-F3.

The Rhodiola rosea extracts were also tested and it was found that theyinhibited cell viability of the HCC cell lines and down-regulate AURKAprotein expression (FIGS. 13A (cell viability) and 13B (down-regulationof AURKA protein expression)).

It is believed that a person of ordinary knowledge in the art where thepresent invention belongs can utilize the present invention to itsbroadest scope based on the descriptions herein with no need of furtherillustration. Therefore, the descriptions and claims as provided shouldbe understood as of demonstrative purpose instead of limitative in anyway to the scope of the present invention.

I/We claim:
 1. An extract with anti-cancer activity, which is extractedwith Dimethyl sulfoxide (DMSO) from a plant of Graptopetalum sp.,Rhodiola sp. or Echeveria sp.
 2. The extract of claim 1, wherein theplant is Graptopetalum paraguayense or Rhodiola rosea.
 3. The extract ofclaim 1, which has a therapeutic effect on liver cancer.
 4. The extractof claim 1, which has a therapeutic effect on Hepatocellular carcinoma(HCC).
 5. A composition comprising a therapeutically effective amount ofthe extract of claim
 1. 6. A method for preventing or treating a cancercomprising administering to a subject in need thereof a therapeuticallyeffective amount of the extract of claim
 1. 7. The method of claim 6,wherein the cancer is liver cancer.
 8. The method of claim 6, whereinthe liver cancer is Hepatocellular carcinoma (HCC).
 9. A fractioncontaining rich anti-cancer components from a plant selected from thegroup consisting of Graptopetalum sp., Rhodiola sp. and Echeveria sp,which is prepared by extracting the plant with dimethyl sulfoxide(DMSO), and then isolating by chromatography to obtain a fraction calledas HH-F3.
 10. The fraction of claim 9, which has effects in causingcytotoxicity and down-regulating AURKA, AURKB, and FLJ10540 expressionin cancer cells.
 11. The fraction of claim 9, wherein a Sephadex LH-20column is used for chromatography.
 12. The fraction of claim 9, whereinthe plant is Graptopetalum paraguayense or Rhodiola rosea.
 13. Thefraction of claim 9, which has a therapeutic effect on liver cancer. 14.The fraction of claim 9, which has a therapeutic effect onHepatocellular carcinoma (HCC).
 15. A pharmaceutical compositioncomprising a therapeutically effective amount of the fraction of claim9, and a pharmaceutically acceptable carrier.
 16. A method forpreventing or treating a cancer comprising administering to a subject inneed thereof a therapeutically effective amount of the fraction of claim9.
 17. The method of claim 16, wherein the cancer is liver cancer. 18.The method of claim 16, wherein the liver cancer is Hepatocellularcarcinoma (HCC).